In a large mixing bowl, using a mixer on medium speed, beat together butter, sugar and vanilla until creamy and smooth. Beat in eggs until well combined. In a medium bowl, sift together flour, cocoa powder, baking powder, baking soda and salt. Beat in the dry ingredients, on low speed, along with water, until just combined. Stir in baking chips until just combined. Chill dough for 1 hour, or until cold.